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Synchrotron X-ray Microdiffraction and Fluorescence Imaging of Mineral and Rock Samples
Published on: June 19, 2018
Los patrones de Widmanstaetten en la josefinita, una roca terrestre que contiene metales
Science (New York, N.Y.)
|November 16, 1979
Resumen
Los patrones de Widmanstaetten, texturas de exsolución por enfriamiento lento, fueron descubiertos en la josefinita, una roca terrestre. Este hallazgo sugiere que la josefinita se originó en el manto de la Tierra.
Área de la Ciencia:
- Geología Geología Geología.
- La mineralogía es la Mineralogía.
- Petrología Petrología.
Sus antecedentes:
- La josefinita es una roca única que contiene metales y que se encuentra en placas de peridotita serpentinizadas.
- Las rocas terrestres por lo general no exhiben patrones Widmanstaetten.
Objetivo del estudio:
- Para investigar la presencia y el origen de los patrones de Widmanstaetten en ejemplares de josephinite.
- Para determinar la historia térmica y la fuente de la josefinita.
Principales métodos:
- Examen microscópico de ejemplares de josefinita del suroeste de Oregón.
- Análisis de las composiciones de fase metálica y texturas de exsolución.
Principales resultados:
- Se identificaron patrones de Widmanstaetten, característicos de la exsolución de enfriamiento lento, en regiones de josefinita menos alteradas.
- La composición a granel indica que el metal homogéneo inicial existió por encima de 500°C.
- Estos patrones no tienen precedentes en ninguna roca terrestre conocida.
Conclusiones:
- Los patrones de Widmanstaetten observados proporcionan una fuerte evidencia del origen del manto de la josefinita.
- La historia térmica de la josefinita es consistente con el enfriamiento lento de una fuente de alta temperatura.
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